#include "Hash.h"
#include <string.h>

uint32_t SuperFastHashInc(const char * data, int len, uint32_t hash);

uint32_t SuperFastHash(const char * data, int len)
{
	return SuperFastHashInc(data, len, len);
}

namespace phnq
{
	namespace phnqlets
	{
		Hash::Hash(char *salt)
		{
			hash = SuperFastHash(salt, strlen(salt));
		}

		void Hash::update(char *data)
		{
			update(data, strlen(data));
		}
	
		void Hash::update(char *data, int len)
		{
			hash = SuperFastHashInc(data, len, hash);
		}
	
		uint32_t Hash::getHash()
		{
			return hash;
		}
	}
}




#undef get16bits
#if (defined(__GNUC__) && defined(__i386__)) || defined(__WATCOMC__) \
  || defined(_MSC_VER) || defined (__BORLANDC__) || defined (__TURBOC__)
#define get16bits(d) (*((const uint16_t *) (d)))
#endif

#if !defined (get16bits)
#define get16bits(d) ((((uint32_t)(((const uint8_t *)(d))[1])) << 8)\
                       +(uint32_t)(((const uint8_t *)(d))[0]) )
#endif

uint32_t SuperFastHashInc (const char * data, int len, uint32_t hash) {
uint32_t tmp;
int rem;

    if (len <= 0 || data == 0) return 0;

    rem = len & 3;
    len >>= 2;

    /* Main loop */
    for (;len > 0; len--) {
        hash  += get16bits (data);
        tmp    = (get16bits (data+2) << 11) ^ hash;
        hash   = (hash << 16) ^ tmp;
        data  += 2*sizeof (uint16_t);
        hash  += hash >> 11;
    }

    /* Handle end cases */
    switch (rem) {
        case 3: hash += get16bits (data);
                hash ^= hash << 16;
                hash ^= data[sizeof (uint16_t)] << 18;
                hash += hash >> 11;
                break;
        case 2: hash += get16bits (data);
                hash ^= hash << 11;
                hash += hash >> 17;
                break;
        case 1: hash += *data;
                hash ^= hash << 10;
                hash += hash >> 1;
    }

    /* Force "avalanching" of final 127 bits */
    hash ^= hash << 3;
    hash += hash >> 5;
    hash ^= hash << 4;
    hash += hash >> 17;
    hash ^= hash << 25;
    hash += hash >> 6;

    return hash;
}
